This invention relates in general to valve construction and in particular to a new and useful slide valve particularly for use with granular and pulverulent substances.
The present invention relates to slide valves having flat valve plates particularly slide valves intended for shutting off pipes for conveying pulverulent or granular substances, and of the kind comprising a housing which contains a passageway for traversal by the substance to be conveyed, and a gaplike guide or guide recess for the valve plate, which guide is centrally situated in the housing and enclosed thereby, the slide valve cooperating with a seal outwardly closing off the guide recess in its blocking position. Herinafter such slide valves will be referred to as "of the kind described".
It is known that difficulties may arise during application of flat slide valves of the kind described in pipes which duct dust-like, granular and pulverulent substances. These difficulties manifest themselves in that particles of a substance may collect in the plate guides and that difficulties then arise primarily during the shutting operation. These difficulties predominantly consist in jamming of the slide valve plate since these trapped particles are denied any path for ejection into the flow. On the other hand, it will be apparent, particularly in the case of sharp-edged particles such as sand, that the slide valve plate slides badly in the area of the housing guide, because these particles stick between the plate and the housing and thereby impede the displacement of the valve plate.